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Background: The perioperative use of immunomodulatory nutrition formulas in patients with head and neck cancer reduces the number of postoperative infections and the length of hospital stay. Objective: An exploratory, randomized, controlled, blind, clinical trial was designed to examine the effect of the preoperative consumption of a new, immunomodulatory, oral nutrition formula in patients with head and neck cancer. Methods: Thirty‐eight patients were randomized to receive either 400 mL/d of either the new immunomodulatory formula (IF) or that commonly used in clinical practice (CF) over 10 days prior to surgery. Thirty‐three patients completed the study. Compliance, tolerance, the length of hospital stay, the incidence of infections and noninfectious complications before discharge, and the same up to 15 and 30 days after discharge were recorded. Results: The percentage of patients who developed infections before discharge was significantly lower in the IF than in the CF group (P = .013), as was the number of infections/100 patients/d (P = .035). The length of hospital stay was significantly shorter in the IF group (P = .001). Both formulas were safe and well tolerated. No other differences were detected. These results suggest preoperative consumption of the new formula to be beneficial for patients with neck and head cancer. Further trials are needed to confirm these results and to test the efficacy of the formula in patients with other conditions. Conclusion: The new formula can be safely prescribed as part of the preoperative treatment of patients with head and neck cancer and might reduce the problem of postoperative infection.  相似文献   
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Thrombocytopenia is the second most common hematological disease during pregnancy and is mainly caused by gestational thrombocytopenia, immune thrombocytopenia, or preeclampsia/HELLP syndrome. This study aims to investigate the causes and pregnancy outcomes of thrombocytopenia in pregnancies with platelet counts below 50 × 109/L. We retrospectively analyzed the pregnancies diagnosed with severe thrombocytopenia at a tertiary care center in western China between January 2009 and December 2017. All enrolled pregnancies were divided into three groups according to the lowest platelet counts: group A (30–50 × 109/L), group B (10–30 × 109/L), and group C (< 10 × 109/L). Maternal and fetal outcomes were observed and compared among these three platelet levels. A total of 533 consecutive pregnancies were included. A relatively large proportion (37.3%, 199/533) of them showed a history of thrombocytopenia before pregnancy or during a previous pregnancy. Most of the women (70.2%, 374/533) received corticosteroids, intravenous immunoglobulin, or platelet transfusion treatments. The incidence of preterm birth < 37 weeks (26.3%, 15/57), cesarean section (93%, 53/57), and neonatal intensive care unit (NICU) admission (31.6%, 18/57) occurred significantly more often in group C than in groups A and B. Neonatal platelet counts were detected in 28.2% of the infants (155/549), and neonatal thrombocytopenia was found in 40.6% of the infants (63/155). Intracranial hemorrhage occurred in 0.9% of the neonates (5/549) throughout the study period, with neonatal nadir platelet counts between 20 × 109/L and 245 × 109/L. One perinatal death occurred in group C. Pregnancies with the lowest platelet counts below 10 × 109/L are more often complicated by preterm birth, cesarean section, and NICU admission compared with those lowest platelet counts 30–50 × 109/L and 10–30 × 109/L. Neonatal intracranial hemorrhage was uncommon in pregnancies with severe thrombocytopenia. Active management should be performed to avoid possible preterm birth and neonatal NICU admission in pregnancies with the lowest platelet counts below 10 × 109/L.

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目的研究二巯基丁二酸修饰的Fe3O4纳米颗粒(dimercaptosuccinic acid-magnetite nanoparticles,DMSA-Fe3O4)对人脐静脉内皮细胞(human umbilical vein endothelial cells,HUVECs)功能的影响。方法利用动态光散射法表征DMSA-Fe3O4的粒径及表面电荷;采用普鲁士蓝染色、邻二氮菲铁定量和透射电镜观察方法研究HUVECs对DMSA-Fe3O4的摄取规律;利用细胞计数试剂盒(Cell Counting Kit-8,CCK-8)检测DMSA-Fe3O4对内皮细胞活性的影响;通过酶联免疫吸附试剂盒测定DMSA-Fe3O4对内皮细胞血管内皮生长因子(vascular endothelial growth factor,VEGF)分泌量的影响。结果HUVECs能够大量吞噬DMSA-Fe3O4,其吞噬量具有孵育时间和剂量依赖性;短时间内所测剂量范围DMSA-Fe3O4对细胞活性无显著影响,但长时间高剂量条件使细胞活性明显降低。此外,在高剂量DMSA-Fe3O4暴露下(200μg/mL),内皮细胞分泌VEGF的量约为对照组的3倍。结论DMSA-Fe3O4易于被HUVECs吞噬;高浓度DMSA-Fe3O4与HUVECs长时间培养使细胞活性降低,并刺激内皮细胞分泌VEGF。  相似文献   
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Retinitis pigmentosa (RP) is the most common manifestation of inherited retinal diseases with high degree of genetic, allelic, and phenotypic heterogeneity. CEP250 encodes the C‐Nap1 protein and has been associated with various retinal phenotypes. Here, we report the identification of a mutation (c.562C>T, p.R188*) in the CEP250 in a consanguineous family with nonsyndromic RP. To gain insights into the molecular pathomechanism underlying CEP250 defects and the functional relevance of CEP250 variants in humans, we conducted a functional characterization of CEP250 variant using a novel Cep250 knockin mouse line. Remarkably, the disruption of Cep250 resulted in severe impairment of retinal function and significant retinal morphological alterations. The homozygous knockin mice showed significantly reduced retinal thickness and ERG responses. This study not only broadens the spectrum of phenotypes associated with CEP250 mutations, but also, for the first time, elucidates the function of CEP250 in photoreceptors using a newly established animal model.  相似文献   
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